by Lindsay H. Jones, USA TODAY Sports

by Lindsay H. Jones, USA TODAY Sports

SANTA CLARA, Calif. -- In the NFL's newest and nastiest rivalry, the hatred is real.

Between the San Francisco 49ers and Seattle Seahawks, who play Sunday at Candlestick Park, the words are harsher and the hits are harder. It might have started as a long-standing feud between a pair of former college coaches, but the rivalry now spans both franchises and their fan bases.

This isn't some faux-rivalry, where players will spew tough talk during the week and hug and exchange jerseys after the game.

"I don't know anybody in here that likes anybody on the Seahawks. If you find one, you let me know," San Francisco guard Alex Boone told USA TODAY Sports as he looked around the Niners' locker room this week.

With a win, Seattle would clinch the NFC West title -- its first division title since 2010.

The 49ers have basically written off winning the division, knowing that even if they win Sunday, it would be nearly impossible to make up enough ground on the Seahawks in the final three weeks.

"This is more of a pride game. This more of a, let's go beat the (crap) out of them game," Boone said.

So how did this so quickly change from just another division game to the best rivalry in the NFL? Easy, Boone said, it started with words.

There's San Francisco head coach Jim Harbaugh, who needled the Seahawks this summer about Seattle's string of drug-related suspensions. There's Pete Carroll, who stood at an interview podium after Seattle's 29-3 win in Week 2 and boasted about how his team had thoroughly shut down the San Francisco offense. There's Seattle's brash-talking cornerback Richard Sherman, who never shuts up. And San Francisco players like Boone and left tackle Joe Staley, who said there is "bad blood" between the teams.

"We don't like them, they don't like us. I don't have a magic answer for why it's so intense, it just is," Staley said Friday. "It's a physical game every time we play, and there's just a lot of bad blood there."

Staley was asked to elaborate about where those negative feelings came from. Staley paused, smiled and deferred.

"A wide variety of things," Staley said. "I'm not going to go there."

Sherman is one of two Seahawks players, with receiver Doug Baldwin, who played for Harbaugh at Stanford, and both have taken great pride in beating their former coach in the past two meetings. Sherman chased Harbaugh down on the field at CenturyLink in September, and patted his former coach on the behind. Sherman was jogging the other way before Harbaugh responded, but Sherman seemed to take the lack of recognition as a slight.

Before the last two meetings, Seattle was perceived as the underdog -- with San Francisco in control of the NFC West last year, and as the defending NFC champion this year.

The situations are reversed now, and Sherman was able to downplay the amount of ill-will his teammates feel for the 49ers. The Niners might not like the Seahawks, but Seattle's players are trying to be ambivalent.

"I feel like they feel that way. We just go out there and play our ballgame, execute. We worry about what we have to do, we don't worry about them," Sherman said.

It's easy for Seattle to be confident, with dominating wins in the past two games against San Francisco, games in which the Seahawks outscored the 49ers 71-16, including a 29-3 win in September in which the Niners offense was thoroughly flustered and frustrated by Seattle's defense.

It was just one of several statement games for Seattle's defense that earned national acclaim after the Seahawks' 34-7 win last week against New Orleans. The 49ers, who won back-to-back division titles on the strength of their own aggressive defense, certainly noticed, and it has ramped up the intensity for this game, safety Donte Whitner said.

The more buzz there is about Seattle's defense, the more San Francisco's defensive players are looking to match it. Whitner said he and his defensive teammates are watching how their Seattle counterparts fare.

"There are just so many positions on the field where you want to go out there and be better than the opposition," Whitner said. "A lot of people don't say that, but you really do. We understand that."

With the relative newness of Seattle to the NFC West -- Seattle switched from the AFC in 2002 -- this doesn't have the history of some of the league's best rivalries, like Green Bay Packers vs. Chicago Bears, or Dallas Cowboys vs. Washington Redskins. But both fan bases have quickly taken to it, and perhaps even escalated it.

Just this week, a San Francisco sports radio station recorded a parody song to the tune of Sweet Caroline with lyrics that mocked Carroll (rhyming "whines" with "Caroline") and the six Seattle players who received suspensions (one was overturned on appeal) for performance-enhancing drugs. Several Seahawks fans, meanwhile, raised more than $2,850 this week via an online petition to pay for a "12th Man" banner to be flown over Candlestick Park before kickoff.

Seattle's fans set a noise record at their stadium when the teams played in September. Candlestick Park doesn't have quite the same acoustic advantages as CenturyLink Stadium, but Harbaugh said he expected his team to receive a boost in their first home game against Seattle in nearly 14 months.

"If this doesn't fire you up, if this doesn't fire up the fans, then what does? I suppose Abraham Lincoln riding across the field with a frock and a top hat, riding a horse, waving an American flag. I doubt that would fire them up, if this game doesn't fire them up," Harbaugh said. "The people that really love football would be fired up by this matchup."

Harbaugh's players insisted they were ready for what should be their most intense regular-season game of the season. Wide receiver Michael Crabtree, who will be playing on his second game of the year after returning from a torn Achilles tendon, said he has to focus on not getting "too hyped."

Boone, meanwhile, is preparing for another slugfest -- a defining trait of recent games between the teams. The Niners have had multiple starters lost to injuries in games against Seattle, including receiver Mario Manningham (ACL in Week 16 last year), tight end Vernon Davis (concussion in Week 16 and a hamstring in Week 2 this year) and nose tackle Ian Williams (season-ending ankle injury in Week 2).

"I enjoy those games. I love being physical, throwing my head into people, maybe a few forearm shivers at the bottom of the pile. Whatever it takes. If I'm getting them, I'm getting it back," Boone said. "It can't be any more ratcheted up than it is right now. This is about to be the biggest stage, you know, the most excited this team has ever been."